For a long time the folding cartons industry has been seeking an alternative solution, which is more economical, ecological, and practical, to overpacks in the form of corrugated cardboard boxes for packaging several individual flat articles which are juxtaposed to form a bundle. These corrugated cardboard boxes can only be reused a very few times, but because of their low cost and wide availability they are the most widespread solution. These boxes receive the flat articles and protect them until they are used, mainly during transport and storage before use.
There are other techniques for packaging flat articles, for example packaging with tensioned straps in which a certain number of flat articles are juxtaposed, in the direction of their thickness, then firmly compressed one against the other by means of one or several tensioned straps. The compressed flat articles form a relatively rigid block, which facilitates handling and reduces the overall dimensions. However this technique can damage the flat articles located at the ends and on which the straps are bent to follow the contour of the block of flat articles. Moreover, the relatively high tension that needs to be maintained to ensure that the flat articles effectively form a solid block can significantly reduce their shape memory and impair their subsequent use. The shape memory of flat articles which have been firmly compressed with tensioned straps can decrease significantly over time and even become zero. Shape memory is the natural tendency of flat articles to remain slightly open when they are new. In the case of folding cartons, this elasticity of the box body, in its flat configuration, may be very useful and even necessary when the boxes are later used in the packaging equipment, in particular automated equipment, used to handle each box before the use for which it has been designed. It is therefore desirable to preserve this shape memory between the stage of manufacture of the flat articles and their use. For these reasons, packaging with tensioned straps is generally only applied to some types of flat articles.
It should also be mentioned that putting flat articles into blocks with tensioned straps does not protect them as well as when they are put into corrugated cardboard boxes. In addition, when these blocks of articles are stacked on top of each other, all the weight of the top blocks is borne directly by the bottom blocks, which can damage the flat articles in the bottom blocks.
There are certain improvements for strap packaging, for example a stacker of bundles of stacked notebooks which inserts a wooden board at each end of the bundle of folding cartons (FR-2869598A1). This technique can avoid damaging the flat articles on the ends, but does not prevent many other disadvantages of strapping.
Other approaches (US-2012031897, EP-2431283, MX-2008003773) enable reusable packages to be formed, but these packages have a generic use and it is not practical to use them for packing flat articles such as folding cartons. In particular they are difficult to adapt to folding carton packaging machines, and are more expensive than corrugated cardboard boxes.
Despite everything that has already been proposed over the years, improvements in the technical field concerned are always and constantly necessary.